Oversight for California's utilities is lacking, audit finds

Electrical equipment managed by California's three largest utilities — PG&E, SCE and SDG&E — ignited over 3,000 fires between 2015 and 2020.

42% of these were caused by an object colliding with an electrical wires that hands overhead, a risk that's highest when lines are bare, rather than insulated.

Most fires caused by electrical equipment burn less than a quarter of an acre. But in areas designated to be at high or extreme fire risk, these fires were 1.67 times more likely to burn more land than a quarter-acre.

All but three of the 15 fires larger than 5,000 acres occured in high- or extreme-risk areas. And all but one of them were caused by PG&E, which has the highest percentage of uninsulated power lines among the state's six utilities, according to the audit report.

Camp Fire, the state's most destructive and deadly wildfire, wasn't even included in PG&E's 2018 report, the auditors identified, so it isn't displayed on this map. Investigators later determined faulty and improperly maintained infrastructure caused the fire.